Entropy Scaling-Based Correlation for Estimating the Self-Diffusion Coefficients of Pure Fluids

• Published in: Industrial & engineering chemistry research 2022-09, Vol.61 (37), p.14033-14050
• Main Authors: Dehlouz, Aghilas, Jaubert, Jean-Noël, Galliero, Guillaume, Bonnissel, Marc, Privat, Romain
• Format: Article
• Language: English
• Subjects: Chemical and Process Engineering; Engineering Sciences; Thermodynamics, Transport, and Fluid Mechanics
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.2c01086

A new model for correlating self-diffusion coefficients is proposed here. It is based on the entropy scaling concept and makes it possible to quantitatively estimate self-diffusion coefficients in any fluid state (subcritical gas and liquid as well as supercritical states). A general relationship between a dimensionless form of the self-diffusion coefficient and a function of the Tv-residual entropy is proposed. This relationship involves thermodynamic properties that were straightforwardly estimated using the I-PC-SAFT and tc-PR equations of state (EoSs). First, the proposed model was parameterized using component-specific parameters. To do so, 72 pure components and ∼2400 pieces of experimental data were considered. Second, a chemical-family parametrization method was used. Four chemical families were defined, and parameter sets valid for all of the compounds of a given family were estimated. Regardless of the considered EoS, the component-specific parametrization enables us to describe data with an average deviation of 7.5%, while when using a chemical-family parametrization, this deviation reaches 9.5%.